Extraction of Water Body Based on LandSat TM5 Imagery - A Case Study in the Yangtze River

A improved method named vegetation normalized difference water index (VNDWI) has been proposed in this paper based on NEW of Xiao Yun-fang(2010), which uses Band 1 and Band 7 and the normalized difference vegetation index (NDVI) in TM5 imagery to construct the VNDWI. This method has been tested in the Yangtze River Basin, and compares the results with other methods is the best. Due to the reflection characteristics differences between water and cloud, NEW method cannot distinguish the differences effectively. However, joins the NDVI parameter, VNDWI can enhance the difference between water and cloud, so it can remove clouds and its shadow noise from water body information without using complicated procedures, which is particular difficult work should be done in pretreatment.